A source close to the Polish Foreign Ministry confirmed to The Associated Press that the ban has taken effect. He spoke on condition of anonymity because he is not authorized to speak on the ministry's behalf.

Spencer previously was banned from the Schengen zone for three years after his 2014 arrest in Hungary, where he had planned to host a conference.

Spencer told The Associated Press he would try to contest a new ban.

"I'm being treated like a criminal by the Polish government. It's just insane," he said. "I haven't done anything. What are they accusing me of?"

Spencer popularized the term "alt-right" to describe a fringe movement that's a loose mix of racist, anti-Semitic and anti-immigration beliefs. In August, he was scheduled to speak at a white nationalist rally in Charlottesville, Virginia, where a car plowed into a crowd of counter-protesters, killing a woman.

Spencer said he cancelled plans to travel to Poland for a far-right conference in Warsaw earlier this month after seeing reports the government was threatening to keep him out of the country.

"It just didn't feel like it was worth it," he said.

Last month, Foreign Minister Witold Waszczykowski described Spencer as someone "who defames what happened during World War II, defames the Holocaust."

"He should not appear publicly, and especially not in Poland," Waszczykowski said.

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